Slow Star Formation in Dense Gas: Evidence and Implications
- M. Krumholz, J. Tan
- Physics
- 12 June 2006
It has been known for more than 30 years that star formation in giant molecular clouds (GMCs) is slow, in the sense that only ~1% of the gas forms stars every free-fall time. This result is entirely…
A General Theory of Turbulence-regulated Star Formation, from Spirals to Ultraluminous Infrared Galaxies
- M. Krumholz, C. McKee
- Physics
- 9 May 2005
We derive an analytic prediction for the star formation rate in environments ranging from normal galactic disks to starbursts and ULIRGs in terms of the observables of those systems. Our calculation…
COLD GASS, an IRAM legacy survey of molecular gas in massive galaxies – I. Relations between H2, H i, stellar content and structural properties
- A. Saintonge, G. Kauffmann, A. Sievers
- Physics
- 8 March 2011
We are conducting COLD GASS, a legacy survey for molecular gas in nearby galaxies. Using the IRAM 30-m telescope, we measure the CO(1-0) line in a sample of similar to 350 nearby (D-L similar or…
COLD GASS, an IRAM legacy survey of molecular gas in massive galaxies - II. The non-universality of the molecular gas depletion time-scale
- A. Saintonge, G. Kauffmann, A. Sievers
- Physics
- 31 March 2011
We study the relation between molecular gas and star formation in a volume-limited sample of 222 galaxies from the COLD GASS survey, with measurements of the CO(1–0) line from the IRAM 30-m…
A UNIVERSAL, LOCAL STAR FORMATION LAW IN GALACTIC CLOUDS, NEARBY GALAXIES, HIGH-REDSHIFT DISKS, AND STARBURSTS
- M. Krumholz, A. Dekel, C. McKee
- Physics
- 19 September 2011
Star formation laws are rules that relate the rate of star formation in a particular region, either an entire galaxy or some portion of it, to the properties of the gas, or other galactic properties,…
THE ATOMIC-TO-MOLECULAR TRANSITION IN GALAXIES. II: H i AND H2 COLUMN DENSITIES
- M. Krumholz, C. McKee, J. Tumlinson
- Physics
- 31 October 2008
Gas in galactic disks is collected by gravitational instabilities into giant atomic–molecular complexes, but only the inner, molecular parts of these structures are able to collapse to form stars.…
A minimum column density of 1 g cm-2 for massive star formation
- M. Krumholz, C. McKee
- Physics, GeologyNature
- 2 January 2008
It is shown that only clouds with column densities of at least 1 g cm-2 can avoid fragmentation and form massive stars, and the existence of a threshold implies that the initial mass function should show detectable variation with environment within the Galaxy.
THE STAR FORMATION LAW IN ATOMIC AND MOLECULAR GAS
- M. Krumholz, C. McKee, J. Tumlinson
- Physics
- 31 March 2009
We propose a simple theoretical model for star formation in which the local star formation rate (SFR) in a galaxy is determined by three factors. First, the interplay between the interstellar…
A general model for the CO–H2 conversion factor in galaxies with applications to the star formation law
- D. Narayanan, M. Krumholz, E. Ostriker, L. Hernquist
- Physics
- 17 October 2011
The most common means of converting an observed CO line intensity into a molecular gas mass requires the use of a conversion factor (XCO). While in the Milky Way this quantity does not appear to vary…
The Formation of Massive Star Systems by Accretion
- M. Krumholz, R. Klein, C. McKee, S. Offner, A. Cunningham
- Physics, GeologyScience
- 20 January 2009
Three-dimensional radiation-hydrodynamic simulations of the collapse of a massive prestellar core are presented and it is found that radiation pressure does not halt accretion, but the instabilities that allow accretion to continue lead to small multiple systems.
...
...